Comment by jerf | Hacker News Reader

Comment by jerf | Hacker News Reader

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Turning the lights on a 3am is a nuisance. Writing

    while true; do turn_on_all_lights $IPADDRESS; done

is enough to ruin your night's sleep. Fighting with the lights that won't go off will probably pump enough adrenaline into your system to wake you up enough that you're not going back to sleep anytime soon.

And why not do that to the entire block of addresses you can reach, of course?

It's no "steal identity, rack up tens of thousands of debt" level of nuisance, but it's enough that some basic security is definitely called for. Given the capability of the devices on both side (i.e. we're not dealing with "embedded" 1MHz processors here), client and server side validation of SSL certificates on an SSL connection, combined with some basic physical security to detect that someone's pried the Android off the wall (this can be something like "seal" stickers; we're going for detection here more than prevention), would have had a pretty good cost/benefit ratio.

(Remember, the goal here isn't to make the security "perfect", merely to make hacking it more expensive than what is being protected, which in this case still isn't that much. Nobody's going to risk being physically fingered as the room that pried out the Android tablet just to screw with lights.)

This might be more amusing:

  while true
    level = 0
      while level <= 100
        set all lights to level%
        level = level + 1
        sleep 5
      sleep 120
    set all lights to 0%
    sleep 1800

The idea is to slowly raise all the lights from 0% to 100%, hoping that because it is gradual it will not wake the person. Then you turn them all suddenly off.

If that succeeds in waking the person, they will wake up in darkness, wondering what the heck woke them up.

More fun with lights: someone at Caltech once modified the wiring of a student's room and the adjacent bathroom so that the light switches in both rooms controlled the lights in both rooms. They they waited in the courtyard that the student's room and the bathroom both overlooked to watch the hilarity that they knew would ensue.

What happened was that the occupant of the room eventually went to bed, turning off his light. Then later someone went to use the bathroom, turning on the bathroom light (and so also the student's light). That woke the student, who got up, turned off the light, and headed back to bed. The guy in the bathroom shouts something, and a few moments later gets his pants under control and goes and turns the light back on and heads back to the stall to resume his business. Meanwhile, bed boy is shouting something and getting up to turn his light back off. What I'm told then happened is that the lights flipped on and off a few more times, with the time between flips getting smaller and smaller, until both guys are just standing at their light switch flipping it repeatedly, before they both go out into the hall to try to figure out what is going on, find each other, and figure it out.

Given the capability of the devices on both side ...

Your're not wrong, but the other point is they are swatting a fly with a sledgehammer. What wrong with a simple light switch for gods sake. Why would a hotel spend hundreds of dollars to do what a $2 device can do more reliably and securely?

There might be significant cost savings in the ability to power off a room remotely instead of having to send someone over when a guest checks out. I would be more worried about the tv, the faucets and air conditioning, though.

Also, some hotels manage to have the tv showing a welcome message when you enter.

Sure. I work in a large university building and can power up/down various systems from my desk for the same reason. But it doesn't require a full tablet computer in each room. These are simple network addressable devices on their own VLAN that allow me to (for example) create an interface that sends a string of commands like a remote control, provided I give proper auth. If you're a regular person in any of the rooms in the building, you can't easily gain access to the VLAN, much less connect to any of the networked controllers in the rooms.

As a result, I can shut things down from my office or set up schedules to do the same. I can monitor usage and save resources (lamp hours on projectors and lighting, etc)

The idea of using a full-on tablet computer is just silly and sounds more like something I'd do while tinkering at home and was looking for a use for some old phone or tablet sitting in a drawer. It's not something I'd put in any enterprise or commercial space.

I've been in many hotels that required the key card to enable power to the room. Some hotels used a simple switch activated by presence of an object in the slot. Many could detect if the NFC tag key was present, but not read the value. Only a few I have seen actually verified that the key was the right key.

I've seen those too. They're quite inconvenient because they actively prevent you from charging your phone or laptop while out of the room. They should leave some marked outlets enabled but usually they only do so for the mini-fridge. And of course "fancy" places build that into a cabinet.

Ask for two card keys and leave one in the room.

At least at the one I stayed at once, you didn't need your room card in the slot, just a card. YMMV.

Though I wouldn't be surprised that the cleaning staff would "clean" it up if you weren't there. Might want to put out the Do-Not-Disturb sign too.

I usually have someone's business card on me, so I'll stick that in the card slot so that I can head to dinner while stuff recharges or the room cools down (for places where the A/C is tied to the same switch). I have yet to see one that's anything more than a simple mechanical switch.

The one I ran into that did that had an outlet that would work when out of the room... in the bathroom, for a rechargeable shaver, presumably. So my laptop got plugged in there...

Prestige.

That's nice, if you're into that. Personally, I'd pay a bit extra not to have this.

I think you are talking thousands not hundreds. They had to pay people to set it up, pay for tablets for every room, and pay for the control devices too.

Maybe the architects/builder forget to lay the cable for the switches and wireless lights can then be a cheaper option.

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